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	        <center><img src="data/pics/tongueForceField.png"  name="Tooth" align="middle">

		<h3>Deformable model of the Tongue</h3></center>

		<div id="orangeText">Description:</div>
		<p align="left">
		We add a deformable model to the tongue. It means the tongue will move and deform depending on the forces applied on it.
		To do this, we use the component <b>TetrahedralCorotanionalFEMForceField</b>. It uses finite element methods to compute the internal forces.
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		<div id="orangeText">Key points:</div>

		<p align="left">
			To add a deformable model in the scene, we need to create a <b>MechanicalObject</b>. All the forces and displacement are computed using an Euler implicit solver (<b>EulerImplicitSolver</b>) for time integration and a Conjugate Gradient linear solver (<b>CGLinearSolver</b>) to solve a linear system. 
			We also need a container to store the tetrahedra (<b>TetrahedronSetTopologyContainer</b>). With all these components, we can add a force field to compute internal forces (<b>TetrahedralCorotanionalFEMForceField</b>).
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		<p align="left">
			The visual model of the tongue is updated because of a mapping (<b>BarycentricMapping</b>) between the deformable model and the visual.
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		<div id="orangeText">Note:</div>

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		<li>
		<p align="left">
			In the current scene, the visual model of the tongue is not displayed, but the deformable model is displayed with the blue tetrahedra.
		</p>
		</li>

		<li>
		<p align="left">
			The tetrahedric mesh of the tongue has been generated using the CGAL plugin in SOFA. Read <a href="dentalSurgery_Annex.scn">this annex</a> to learn more about mesh generation using CGAL plugin.
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		</li>

		<li>
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			The mass chosen for the deformable model of the tongue is a DiagonalMass. It has been chosen to show the diversity of masses available in SOFA. This kind of mass computes the mass matrix with non uniform diagonal values, depending on the tetrahedra size.
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		<center><h3><a href="dentalSurgery_08.scn">Next</a></center></h3>
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